If the temperature changes in a chemical reaction, what has occured?

A) energy was destroyed

B) energy was created

C) there was no energy transfer

D) energy was transferred

What is the order of which electrons start filling the orbitals

What is the mass of a sample of copper that contains 4.78 x 1023 atoms?

Do ionic compounds conduct electricity as: a. solids? b. liquids? c. aqueous solutions (when the ionic compounds are dissolved in water) ?

Nitric oxides, no and no2, contribute to air pollution, acid rain, and the depletion of the ozone layer. after no forms in the combustion chamber of an automobile engine, it reacts further with oxygen to form no2. the reaction is given by

A laser produces 20.0 mW of light. In 1.00 hr, the laser emits 1.51*1020 photons. What is the wavelength of the laser?

How are sex chromosomes different from other chromosomes

If we place the like poles of two magnets facing each other what will happen? A. Nothing B. They will both become negative. C. They will attract each other. D. They will repel each other.

What is the percentage of water to the nearest tenth in this compound? Ba (OH) 2 * 8H2O

What term describes the specific amount of time required for half of a radioactive substance to become stable

H2 + N2 - - - > NH3 For this unbalanced chemical equation, what is the coefficient for hydrogen when the equation is balanced? A. 1 B. 2 C. 3 D. 4